1. Field of the Invention
The present invention relates to a feed control system of the type wherein the rotation of a servomotor is controlled to move a movable body to an objective position designated by command data.
2. Description of the Prior Art
In a known feed control system for an industrial robot, an integrator is provided in a drive circuit which drives a servomotor for moving a working head. When the difference between an objective position and a present position of the working head is small, but the small difference is continued, the integrator operates to gradually increases an electric power supplied to the servomotor. Thus, the servomotor is rotated with a large torque so that the positioning accuracy of the working head can be heightened.
However, even when the working head interferes with an obstruction just before reaching an objective position, the electric power supplied to the servomotor is gradually increased by the operation of the integrator after the occurrence of the interference. The servomotor is thus caused to generate a large torque, and en excess force is exerted upon the working head, thereby resulting in destroying the working head.